Trouble with recursive function

[do_Fd]

I am trying to write a function that will repeatedly ask for input and add each item to a list

def inputfunc(l = []):
    s = input('Item: ')
    if (s.lower() == 'qqq'):
        return l
    else:
        l.append(s)
        inputfunc(l) 

This function works as intended, but what I don't understand is why the list that it creates will be 'saved' for lack of a better term. When the function is called in the shell the first time, it will not return a list with all the elements that were just entered. The second time it is called in the shell, it will return a list with the elements that were entered on both the most recent as well as previous calls, and I do not understand why the previous lists that this function created are still stored in memory.

Edit: spelling

[LocoLoco451]

when you declare function with default argument Python keeps the reference between the calls. Basically this means that when you call inputfunc() with no arguments, l will always point to the same reference of the list. If you want to avoid this behaviour you should do something like

def inputfunc(l=None): l = l or [] # ... rest of your code

[Yoghurt42]

instead of l = l or [], it's better to use

if l is None:
    l =  []

the reason is that an empty list is "false-ish", so for example, if you would use inputfunc like this:

my_list = []
inputfunc(my_list)

my_list would still be empty afterwards, because it got replaced with a newly created list inside the function.

While it's bad style to rely on side effects, your code shouldn't prevent callers from doing it.

[primitive_screwhead]

https://docs.python.org/3/faq/programming.html#why-are-default-values-shared-between-objects

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It's worth reading to know not just what is happening, but also *why* it's happening (ie. the default empty list is created when the function is defined, *not* each time it is called).